Wunda manifolds

[RichJ]

Hi

 

I've been in contact with Wunda re using their 'Premium stainless steel Manifolds' with radiators as opposed to UFH.

 

They've come back with 2 concerns:

 

1, the flow rates in the radiators might be too low

2, running the manifold at the higher temps required for radiators (50+ degrees) might affect the life of the components

 

Are there concerns valid? I haven't heard anyone of the forums here refer to problems like these...

Edited December 5, 2023 by RichJ

[MikeGrahamT21]

I vaguely remember setting mine at 2 lpm on each circuit bar the bypass (bathroom) and the boiler pump is set to 80% max flow. Been running for around 6 years so far with some big vertical bar radiators and a couple of standard single rads, no complaints from me.

 

temperature won’t affect the manifold itself, only thing I can see ever wearing out is the flow rate meters which can always be replaced, and you’ll find they get a lot dirtier quickly with rads, mine are black inside and can’t read the rate anymore, really need to clean them at some point 😂 

no other components in there you wouldn’t find in the rest of the heating system.

 

ran for most of the 6 years at 55C, just moved to 45C this autumn

 

[RichJ]

Hi again Mike

 

I've ordered a 6 port manifold from Wunda.. should be installing it in my cellar/basement to cover the downstairs and basement radiators as a test before tackling the upstairs rads.

 

Did you get any problems when the boiler pump was set to a lower speed?

 

Oh and did you run 22mm copper as the flow/return to the manifolds (then 16mm plastic to the radiators)? I'm wondering whether to use 25mm plastic for the flow/return in my case, but I have no idea what 25mm plastic is like to work with.

Edited December 9, 2023 by RichJ

[HughF]

10 hours ago, RichJ said:

Hi again Mike

 

I've ordered a 6 port manifold from Wunda.. should be installing it in my cellar/basement to cover the downstairs and basement radiators as a test before tackling the upstairs rads.

 

Did you get any problems when the boiler pump was set to a lower speed?

 

Oh and did you run 22mm copper as the flow/return to the manifolds (then 16mm plastic to the radiators)? I'm wondering whether to use 25mm plastic for the flow/return in my case, but I have no idea what 25mm plastic is like to work with.

Beware that unlike 16/20/32 pex-al, there are both 25 & 26mm covering the 22 equivalent size.

[MikeGrahamT21]

15 hours ago, RichJ said:

Hi again Mike

 

I've ordered a 6 port manifold from Wunda.. should be installing it in my cellar/basement to cover the downstairs and basement radiators as a test before tackling the upstairs rads.

 

Did you get any problems when the boiler pump was set to a lower speed?

 

Oh and did you run 22mm copper as the flow/return to the manifolds (then 16mm plastic to the radiators)? I'm wondering whether to use 25mm plastic for the flow/return in my case, but I have no idea what 25mm plastic is like to work with.

not had any issues though lowest pump speed I’ve set is 80%.

 

yeah it’s all 16mm to rads, and then 22mm plastic both from and to boiler with the last 2m in 22mm copper. If you can make 25mm work, it wouldn’t be a bad thing with heat pumps in mind, and then just a brass converter to bring it down to 22mm to fit your boiler pipework 

[RichJ]

2 hours ago, MikeGrahamT21 said:

Yeah it’s all 16mm to rads, and then 22mm plastic both from and to boiler with the last 2m in 22mm copper. If you can make 25mm work, it wouldn’t be a bad thing with heat pumps in mind, and then just a brass converter to bring it down to 22mm to fit your boiler pipework 

 

So 22mm plastic as in Hep2o?

 

[MikeGrahamT21]

2 hours ago, RichJ said:

 

So 22mm plastic as in Hep2o?

 

yes, I forget which exact type I used but yeah it was just standard PEX pipe